Torque coupling assemblies and related systems and methods

ABSTRACT

Force coupling or torque coupling assemblies, apparatuses, systems, and methods include assemblies that each include superhard contact elements. At least some of the superhard contact elements may be configured to remain in contact with each other when a force is applied between the assemblies.

TECHNICAL FIELD

This application relates to force coupling assemblies (e.g., torque coupling assemblies) including superhard contact elements and related systems and methods.

BACKGROUND

Coupling mechanisms or assemblies are commonly used in a variety of mechanical applications. For example, subterranean drilling systems, turbomachinery, hydroelectric plants, windmills, cranes, turbine generators, pumps, automotive parts or component, marine propulsion components, and power plant machinery may utilize coupling assemblies to couple a driven shaft to other componentry (e.g., other shafts, tools, etc.).

As one example, a subterranean drilling system may include one or more coupling assemblies that are operably coupled to an output shaft of the downhole drilling motor for distributing forces or loads (e.g., torque coupling between rotating components) generated during drilling operations. The output shaft may be coupled to one or more additional components (e.g., including the motor) that require force couplings that can withstand the torque applied by the motor. Further, in extreme environments, such as in a borehole, the caustic and/or corrosive conditions may require that the force couplings be sealed from environmental elements, such as from the drilling fluid used during a downhole operation. Further, other industrial processes and/or machinery involve the use of caustic fluids, abrasive fluids, and/or acidic fluids. These types of fluids may increase the amount of wear on the movable components of a system. The increased wear may result in increased maintenance and repair costs or require the early replacement of equipment.

During drilling operations or other operations involving one or more rotating components, such as shafts, the output shaft that transfers rotational torque from a motor to a drill bit or other tool or component may be deflected at various angles relative to the axis of rotation. Over time, such repeated deflection of the output shaft may apply additional forces and loads to force couplings attached to the output shaft as the force couplings and/or the shaft become displaced from a central axis about which the shaft is rotating.

SUMMARY

Embodiments of the instant disclosure may be directed to force coupling assemblies, systems, and methods. According to some embodiments, a torque coupling assembly may include an inner assembly comprising an inner support ring positioned circumferentially about an inner ring axis and a first plurality of superhard contact elements coupled to the inner support ring, where each of the first plurality of superhard contact elements have a superhard contact surface. The torque coupling assembly may further include an outer assembly comprising an outer support ring positioned circumferentially about an outer ring axis and a second plurality of superhard contact elements coupled to the outer support ring, where each of the second plurality of superhard contact elements have a superhard contact surface. The superhard contact surface of at least one of the second plurality of superhard contact elements is configured to contact and transfer a torque to a respective superhard contact surface of at least one of the first plurality of superhard contact elements when a rotational force is applied between the inner assembly and the outer assembly.

According to some embodiments, a force coupling assembly may include a first assembly comprising a first support structure positioned circumferentially around a first structure axis and one or more contact elements coupled to the first support structure, where the one or more contact elements each have a superhard contact surface. The force coupling assembly may further include a second assembly comprising a second support structure positioned circumferentially around a second structure axis and one or more contact elements coupled to the second support structure, where the one or more contact elements each have a superhard contact surface. The superhard contact surface of each of the one or more contact elements coupled to the second support structure oppose a respective one of the one or more contact elements coupled to the first support structure. The superhard contact surface of at least one of the one or more contact elements coupled to the second support structure is configured to engage with and remain substantially stationary relative to a respective one or more contact elements coupled to the first support structure when a force is applied between the first assembly and the second assembly.

According to some embodiments a method of transfer torque between components of a rotating system includes applying torque to a shaft in order to rotate the shaft about an axis of rotation; and transferring the torque to another component coupled to the shaft with at least one torque coupling assembly. The transferring the torque comprises applying the torque through a first ring coupled to the shaft, the first ring having one or more superhard coupling elements coupled to the first ring and transferring the torque from the first ring through the one or more superhard coupling elements coupled to the first ring to one or more superhard coupling elements coupled to a second ring that is coupled to the another component. The method further includes rotating the another component with the transferred torque.

Features from any of the above-mentioned embodiments may be used in combination with one another in accordance with the general principles described herein. These and other embodiments, features, and advantages will be more fully understood upon reading the following detailed description in conjunction with the accompanying drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate a number of exemplary embodiments and are a part of the specification. Together with the following description, these drawings demonstrate and explain various principles of the instant disclosure.

FIG. 1 is a perspective view of a force coupling assembly according to an embodiment of the disclosure.

FIG. 2 is a cross-sectional view of the force coupling assembly shown in FIG. 1 .

FIGS. 3 through 13 are cross-sectional views of a portion of a force coupling assembly according to embodiments of the disclosure.

FIG. 14 is a partial cut-away perspective view of a subterranean drilling system including one or more force coupling assembly according to an embodiment of the disclosure.

DETAILED DESCRIPTION

Embodiments of the instant disclosure is directed to force coupling assemblies and force coupling assemblies (e.g., torque coupling assemblies) including superhard contact elements. The force coupling assemblies may be configured to transfer a load between components (e.g., to transfer torque between two or more laterally or radially arranged rings). Such force coupling assemblies may be used in a variety of applications, including subterranean drilling systems, directional drilling systems, turbine generators, windmills, cranes, machinery, pumps, automotive and marine components, and any other suitable applications, without limitation.

The terms “superhard,” as used herein, may refer to any material having a hardness of known superhard materials, for example, a hardness that is at least equal to a hardness of tungsten carbide. For example, a superhard article may represent an article of manufacture, at least a portion of which may exhibit a hardness that is equal to or greater than the hardness of tungsten carbide.

As used herein, relational terms, such as “first,” “second,” “top,” “bottom,” etc., are generally used for clarity and convenience in understanding the disclosure and accompanying drawings and do not connote or depend on any specific preference, orientation, or order, except where the context clearly indicates otherwise.

As used herein, the term “and/or” means and includes any and all combinations of one or more of the associated listed items.

As used herein, the terms “vertical,” “lateral,” and “radial” refer to the orientations as depicted in the figures.

As used herein, the term “substantially” or “about” in reference to a given parameter means and includes to a degree that one skilled in the art would understand that the given parameter, property, or condition is met with a small degree of variance, such as within acceptable manufacturing tolerances. For example, a parameter that is substantially met may be at least 90% met, at least 95% met, at least 99% met, or even 100% met.

Wear-resistant, superhard materials may be utilized for contact elements utilized in force coupling assemblies. The force coupling assembly may include structures positioned in opposition (e.g., an inner structure and an outer structure at least partially receiving the inner structure, such as concentric rings) that are each configured to accept a number of superhard contact elements. In some embodiments, each superhard contact element may include a polycrystalline diamond compact (PDC) having one or more polycrystalline diamond (PCD) layers formed on a substrate, such as a cemented tungsten carbide substrate. However, as discussed above and below, other superhard materials may be implemented. In some embodiments, the structures formed as rings defining the force coupling assembly may be annular rings or other polygonal shaped rings.

One or more superhard contact elements may be attached to the rings by press-fitting, brazing, or through other suitable methods of attachment. Contact elements attached to one of the rings may have superhard contact surfaces configured and oriented radially outward to contact opposing superhard contact surfaces of contact elements attached to the other ring, for example, where the other ring at least partially radially surrounds the first ring.

In use, at least some of the superhard contact surfaces of contact elements of the rings may interact (e.g., are placed in contact) in order to substantially secure the rings relative to each other (e.g., such that the rings exhibit little to no movement relative to each other). As the rings remain in contact, forces (e.g., torque) may be transmitted between the rings. Such force may be utilized to couple a force applied to a first component to a second component of a system or assembly. For example, the rings of the force coupling assembly may couple a torque applied to a first rotating component (e.g., by a motor) to a second component in order to rotation the second component.

FIG. 1 is a perspective view of a force coupling assembly 100 (e.g., in a radially opposing configuration to transfer rotational energy, such as torque) and FIG. 2 is a cross-sectional view of the force coupling assembly 100. As illustrated in FIGS. 1 and 2 , the force coupling assembly 100 may be configured to primarily transfer forces or loads (e.g., torque) between the structures of the force coupling assembly 100. For example, the force coupling assembly 100 may be configured to transfer force where a majority of the force is transferred through the force coupling assembly 100 via contact between first force coupling assembly 102 and second force coupling assembly 108 (e.g., in response to forces applied in a lateral or radial direction to either/both of first force coupling assembly 102 and second force coupling assembly 108).

As depicted, force coupling assembly 100 may comprise a first force coupling assembly 102 (e.g., an inner structure or assembly) having contact elements 104 (e.g., superhard contact elements) coupled to a first support structure 106 and arranged about a central point or inner axis. The contact elements 104 may be positioned in the first support structure 106 at a substantially similar or the same angle relative to the inner axis. For example, centerlines of the contact elements 104 may each be set at a direction transverse to the inner axis (e.g., substantially perpendicular to). In additional embodiments, the centerlines of the contact elements 104 may be set at an oblique angle relative to the inner axis where the contact element may also at least partially support forces along the inner axis (e.g., axial loadings).

Force coupling assembly 100 may additionally comprise a second force coupling assembly 108 (e.g., an outer structure or assembly) having contact elements 110 (e.g., superhard contact elements) coupled to a second support structure 112 and arranged about a central point or axis. As depicted, a portion of the first support structure 106 of the first force coupling assembly 102 may be received in the second support structure 112 of the second force coupling assembly 108. The contact elements 110 may be positioned in the second support structure 112 at a substantially similar or the same oblique angle relative to the inner axis, such as, for example, at complementary angles to the angles discussed above in relation to the contact elements 104 (e.g., substantially perpendicular to the inner axis or at an oblique angle relative thereto).

As depicted, the support structures 106, 112 may be annular (e.g., rings, ovals, etc.) or may comprise polygonal shapes, or other suitable shapes, without limitation.

In some embodiments, first force coupling assembly 102 and second force coupling assembly 108 may be configured to remain generally stationary relative to one another (e.g., during loading). For example, while some movement between the first force coupling assembly 102 and the second force coupling assembly 108 may occur during initial loading (e.g., during the start of rotary motion), the first force coupling assembly 102 and the second force coupling assembly 108 may remain generally stationary once the forces increase to a selected amount (e.g., once the contact elements 104 are adequately engaged with the contact elements 110 in order to effectively transfer torque between the contact elements 104, 110. In some embodiments, the first force coupling assembly 102 and the second force coupling assembly 108 may initially rotate relative to each other only a limited magnitude of degrees or less (e.g., less than 1 degree, less than 2 degrees, less than 3 degrees, less than 4 degrees, or less than 5 degrees) during loading. For example, the first force coupling assembly 102 and the second force coupling assembly 108 may initially rotate relative to each other less than 1 degree to 15 degrees, less than a quarter of a circle, a minor portion of a circle (e.g., less than 180 degrees), etc.

In some embodiments, the first force coupling assembly 102 and the second force coupling assembly 108 may initially rotate up to a full relative revolution (e.g., less than a full rotation) between the assemblies 102, 108. For example, where the contact elements 104, 110 are positioned only on one radial side of a respective support structure 106, 112, the first force coupling assembly 102 and the second force coupling assembly 108 may initially rotate until the contact elements 104, 110 are engaged with each other.

Regardless of the amount of relative rotation, the contact elements 104, 110 are configured to eventually engage in a generally stationary configuration (e.g., not moving relative to each other) under contact loading where forces may be applied between the contact elements 104, 110 (e.g., under a rotational force or moment).

First force coupling assembly 102 and second force coupling assembly 108 may each be arranged circumferentially around a central axis (e.g., longitudinal axis 114). The longitudinal axis 114 may comprise a rotational axis about which first force coupling assembly 102 and second force coupling assembly 108 engage rotationally. However, a rotational axis of first force coupling assembly 102 and second force coupling assembly 108 may not be aligned with longitudinal axis 114 at all times during operation. For example, during operation, second force coupling assembly 108 may be circumferentially centered about a longitudinal axis 114 while the first force coupling assembly 102 is circumferentially centered about and/or rotates about an axis that is oriented at an angle (and/or slightly misaligned) with respect to the longitudinal axis 114.

First support structure 106 may comprise an outer surface 116 facing radially outward that opposes an inner surface 118 of the second support structure 112 that faces radially inward with respect to the longitudinal axis 114.

Force coupling assembly 100 may include a central aperture 120 defined the first support structure 106 and/or the second support structure 112 that may receive a shaft (e.g., a motor shaft or a pump shaft). As depicted, aperture 120 may be generally centered about longitudinal axis 114.

First support structure 106 may be configured to receive one or more contact elements 104 (e.g., at least one including a superhard material) that may each be attached within a corresponding recess 122 defined in first support structure 106. Second support structure 112 may also be configured to receive one or more contact elements 110 (e.g., at least one including a superhard material) that may each be attached within a corresponding recess 124 defined in second support structure 112. Each contact element 104 may be flush with or may extend beyond outer surface 116 of first support structure 106 by a selected distance. Similarly, each contact element 110 may be flush with or may extend beyond inner surface 118 of second support structure 112 by a selected distance. Each of contact elements 104 and contact elements 110 may be fixedly secured within a corresponding recess 122, 124, respectively, through brazing, press-fitting, threaded attachment, pin attachment, bonding, frictional engagement, and/or by any other suitable attachment mechanism or structure, combinations thereof, without limitation.

Any suitable number of contact elements 104 and contact elements 110 may be secured, respectively, to first support structure 106 and second support structure 112 (e.g., one or more elements 104, 110). For example, contact elements 104 may each be secured within the corresponding recess 122 defined in first support structure 106 while a similar or the same number of contact elements 110 may each be secured within the corresponding and complementary recess 124 defined in second support structure 112. First force coupling assembly 102 may comprise the same number or a different number of contact elements 104 in comparison with the number of contact elements 110 included in second force coupling assembly 108. Additionally, contact elements 104 may have substantially the same dimensions (e.g., diameters) and/or overall shape as contact elements 110 or different dimensions and/or overall shape than contact elements 110.

First support structure 106 and second support structure 112 may each be made from a variety of different materials. For example, first support structure 106 and/or second support structure 112 may comprise a metallic material (e.g., carbon steel, titanium or titanium alloys, tungsten or tungsten alloys, aluminum or aluminum alloys, or stainless steel, etc.), a carbide material (e.g., tungsten carbide, silicon carbide, etc.), or any other suitable material. In some embodiments, first support structure 106 and/or second support structure 112 may be made of a material with relatively high thermal conductivity (e.g., tungsten carbide or cobalt-cemented tungsten carbide). Contact elements 104, 110 may each abut or contact a respective support structure 106, 112 over a selected (e.g., a substantial) surface area of the contact element 104, 110.

In some embodiments, first support structure 106 and/or second support structure 112 may include an erosion-resistant and/or abrasion-resistant coating applied thereto. For example, an erosion-resistant and abrasion resistant coating may include a coating including, for example, a urethane rubber or other suitable coating, without limitation. In other embodiments, a hardfacing coating (e.g., tungsten carbide hardfacing) may be applied to first support structure 106 and/or second support structure 112 by any suitable method, including, without limitation, flame spraying, welding HVOF (high velocity oxy-fuel coating spraying), and/or laser cladding.

In some embodiments, contact elements 104 may be positioned and oriented on first support structure 106 and contact elements 110 may be positioned and oriented on second support structure 112 such that contact surfaces of contact elements 104 contact opposing contact surfaces of contact elements 110. When first force coupling assembly 102 and second force coupling assembly 108 are assembled together, contact surfaces of contact elements 104 and the opposing contact surfaces of contact elements 110 may bear against each other and may initially move relative to each other as first force coupling assembly 102 rotates relative to second force coupling assembly 108 until a selected amount of force is applied between the contact elements 104, 110. In some embodiments, the contact elements 104, 110 may be substantially fixed relative to each other such that no radial or axial movement may occur between the contact elements 104, 110.

As will be described in greater detail below, contact elements 104 and contact elements 110 may comprise various surface shapes and configurations for achieving desired contact and/or freedom/limitation of movement between opposing contact surfaces.

As noted above, an interface between the contact elements 104 and contact elements 110 may define an angle with respect to the longitudinal axis 114 (e.g., may be substantially parallel with the longitudinal axis 114). In some embodiments, the angle of the interface between the contact elements 104, 110 may be selected (e.g., greater than 0 degree and less than or substantially equal to 90 degrees) relative to the longitudinal axis 114.

FIG. 3 is a cross-sectional view of a portion of a force coupling assembly 100 including contact elements 104, 110 on opposing support structures, respectively (e.g., the first force coupling assembly 102 and the second force coupling assembly 108 as shown in FIGS. 1 and 2 ).

As illustrated in FIG. 3 , a portion of contact element 104 extending from or substantially flush with first support structure 106 may comprise a contact surface 126 (e.g., a superhard contact surface). The contact surface 126 may comprise any suitable shape, without limitation (e.g., a planar shape, a rounded or curved shape, combinations thereof, etc.). For example, contact surface 126 may comprise an at least partially rounded surface, such as a convex partial-cylindrical surface or partial-spherical surface. Further, in some embodiments, a portion of contact element 110 may comprise a contact surface 136 which at least partially corresponds to at least a portion of contact surface 126. In some embodiments, the contact surface 136 may exhibit a ramped, concave, or tapered shape portion with a central lower portion that extends along a diameter of the contact surface 136 and is bordered by two opposing higher portions positioned at two outer radial sections of the contact elements 110.

As depicted, the contact surface 126 may exhibit a curvature (e.g., a major or maximal curvature that is greater than zero) substantially with respect to a first reference only one axis (e.g., a radial axis extending through the center/centroid of the contact surface 126)as opposed to a spherical surface that exhibits a similar curvature with respect to more than one reference axis (e.g., more than one radial axis extending through the center/centroid of the contact surface 126) defined radial axis. With respect to another reference axis of the contact surface 126 that is transverse (e.g., perpendicular) to the first reference axis, curvature may be minimal (e.g., no) curvature (e.g., approaching or equal to zero). The contact elements 104 may each exhibit a ramped or tapered shape with a central higher portion that extends along a diameter of the contact surface 126 (e.g., from a first lateral side to a second opposing lateral side). The central higher portion (e.g., central curved portion) is bordered on opposing lateral sides by two opposing lower portions (e.g., two ramp potions) positioned at two outer lateral sections of the contact elements 104.

As further shown in FIG. 3 , a portion of contact element 110 extending from or substantially flush with second support structure 112 may comprise a contact surface 136 (e.g., a superhard contact surface). The contact surface 136 of one or more of the contact elements 110 (e.g., each contact element 110) may comprise an at least partially rounded or ellipsoidal convex surface. For example, the contact surface 136 may comprise an at least partially convex rounded shape. In some embodiments, the contact surfaces 136 of the contact elements 110 may comprise a partially ellipsoidal surface, a partially cylindrical surface (e.g., a convex cylindrical surface), and/or partially spherical shape.

As depicted, contact surface 136 may comprise a convex, partially ellipsoidal or substantially partially ellipsoidal surface shape. For example, a cross-sectional view of contact element 110 taken along a plane parallel to the central element axis may have a convex, partially circular or substantially partially circular profile for contact surface 136 as shown in FIG. 3 . In some embodiments, contact surface 136 may comprise a substantially partially spherical surface shape. In such embodiments, each cross-sectional view of contact element 110 taken along a plane intersecting a central element axis of the contact element 110 may have substantially the same or similar profile.

Contact elements 104, 110 may also include a chamfer 132 between a side surface and contact surfaces 126, 136. Chamfer 132 may comprise an angular, sloped, and/or rounded edge formed at the intersection of superhard side surface and contact surfaces 126, 136. Any suitable surface shape may be formed at the intersection of superhard side surface and contact surfaces 126, 136, such as those disclosed in U.S. Pat. No. 8,708,564, the disclosure of which is incorporated herein in its entirety by this reference. Any other suitable surface shape may also be formed at the intersection of superhard side surface and contact surfaces 126, 136, including, without limitation, an arcuate surface (e.g., a radius, an ovoid shape, or any other rounded shape), a sharp edge, multiple chamfers/radii, a honed edge, and/or combinations of the foregoing.

Contact elements 104, 110 may comprise any suitable size, shape, and/or geometry, without limitation. In some embodiments, the contact elements 104, 110 may have widths (e.g., diameters) of between 6 mm to 26 mm in a generally cylindrical shape or another shape (e.g., oval, polygonal, etc.). In some embodiments, the thickness of the superhard table 128 may be greater than 0.50 millimeters (e.g., 1 mm to 2mm, 2 mm to 3 mm, 3 mm to 4 mm, or greater than 4 mm).

In some embodiments, contact elements 104, 110 may each comprise a superhard table 128 affixed to or formed upon a substrate 130. Where implemented, the substrate 130 of the contact elements 104, 110 may comprise any suitable material on which the superhard table 128 may be formed. In at least one embodiment, substrate 130 may comprise a cemented carbide material, such as a cobalt-cemented tungsten carbide material and/or any other suitable material. In some embodiments, substrate 130 may include a suitable metal-solvent catalyst material, such as, for example, cobalt, nickel, iron, and/or alloys thereof. Substrate 130 may also include any suitable material including, without limitation, carbides such as titanium carbide, tungsten carbide, niobium carbide, tantalum carbide, vanadium carbide, chromium carbide, and/or combinations of any of the preceding carbides cemented with iron, nickel, cobalt, and/or alloys thereof. Superhard table 128 may be formed of any suitable superabrasive and/or superhard material or combination of materials, including, for example, PCD. Any of the superhard tables disclosed herein may also comprise polycrystalline diamond materials, such as those disclosed in U.S. Pat. No. 7,866,418, the disclosure of which is incorporated herein, in its entirety, by this reference. According to additional embodiments, superhard table 128 may comprise cubic boron nitride, silicon carbide or nitride, polycrystalline diamond, diamond slugs, other carbides or nitrides (e.g., tungsten carbide) and/or mixtures or composites including one or more of the foregoing materials, without limitation.

Superhard table 128 of contact elements 104, 110 may be formed using any suitable technique. According to some embodiments, superhard table 128 may comprise a PCD table fabricated by subjecting a plurality of diamond particles to a high pressure, high temperature (HPHT) sintering process in the presence of a metal-solvent catalyst (e.g., cobalt, nickel, iron, or alloys thereof) to facilitate intergrowth between the diamond particles and form a PCD body comprised of bonded diamond grains that exhibit diamond-to-diamond bonding therebetween. For example, the metal-solvent catalyst may be mixed with the diamond particles, infiltrated from a metal-solvent catalyst foil or powder adjacent to the diamond particles, infiltrated from a metal-solvent catalyst present in a cemented carbide substrate, or combinations of the foregoing. The bonded diamond grains (e.g., sp3-bonded diamond grains), so-formed by HPHT sintering the diamond particles, define interstitial regions with the metal-solvent catalyst disposed within the interstitial regions of the as-sintered PCD body. The diamond particles may exhibit a selected diamond particle size distribution.

Following sintering, various materials, such as a metal-solvent catalyst, remaining in interstitial regions within the as-sintered PCD body may reduce the thermal stability of superhard table 128 at elevated temperatures. In some examples, differences in thermal expansion coefficients between diamond grains in the as-sintered PCD body and a metal-solvent catalyst in interstitial regions between the diamond grains may weaken portions of superhard table 128 that are exposed to elevated temperatures, such as temperatures developed during operation. The weakened portions of superhard table 128 may become excessively worn and/or damaged during operation.

Removing the metal-solvent catalyst and/or other materials from the as-sintered PCD body may improve the heat resistance and/or thermal stability of superhard table 128, particularly in situations where the PCD material may be exposed to elevated temperatures. A metal-solvent catalyst and/or other materials may be removed from the as-sintered PCD body using any suitable technique, including, for example, leaching. In at least one embodiment, a metal-solvent catalyst, such as cobalt, may be removed from regions of the as-sintered PCD body, such as regions adjacent to the working surfaces of superhard table 128. Removing a metal-solvent catalyst from the as-sintered PCD body may reduce damage to the PCD material of superhard table 128 caused by expansion of the metal-solvent catalyst.

At least a portion of a metal-solvent catalyst, such as cobalt, as well as other materials, may be removed from at least a portion of the as-sintered PCD body using any suitable technique, without limitation. For example, chemical and/or gaseous leaching may be used to remove a metal-solvent catalyst from the as-sintered PCD body up to a desired depth from a surface thereof. The as-sintered PCD body may be leached by immersion in an acid, such as aqua regia, nitric acid, hydrofluoric acid, or subjected to another suitable process to remove at least a portion of the metal-solvent catalyst from the interstitial regions of the PCD body and form superhard table 128 comprising a PCD table. For example, the as-sintered PCD body may be immersed in or exposed to the acid for about 2 to about 7 days (e.g., about 3, 5, or 7 days) or for a few weeks (e.g., about 4 weeks) depending on the process employed.

Even after leaching, a residual, detectable amount of the metal-solvent catalyst may be present in the at least partially leached superhard table 128. It is noted that when the metal-solvent catalyst is infiltrated into the diamond particles from a cemented tungsten carbide substrate including tungsten carbide particles cemented with a metal-solvent catalyst (e.g., cobalt, nickel, iron, or alloys thereof), the infiltrated metal-solvent catalyst may carry tungsten and/or tungsten carbide therewith and the as-sintered PCD body may include such tungsten and/or tungsten carbide therein disposed interstitially between the bonded diamond grains. The tungsten and/or tungsten carbide may be at least partially removed by the selected leaching process or may be relatively unaffected by the selected leaching process.

In some embodiments, only selected portions of the as-sintered PCD body may be leached, leaving remaining portions of resulting superhard table 128 in an unleached state. For example, some portions of one or more surfaces of the as-sintered PCD body may be masked or otherwise protected from exposure to a leaching solution and/or gas mixture while other portions of one or more surfaces of the as-sintered PCD body may be exposed to the leaching solution and/or gas mixture. Other suitable techniques may be used for removing a metal-solvent catalyst and/or other materials from the as-sintered PCD body or may be used to accelerate a chemical leaching process. For example, exposing the as-sintered PCD body to heat, pressure, electric current, microwave radiation, and/or ultrasound may be employed to leach or to accelerate a chemical leaching process, without limitation. Following leaching, at least a portion of superhard table 128 may comprise a volume of PCD material that is substantially free of a metal-solvent catalyst.

The plurality of diamond particles used to form superhard table 128 comprising the PCD material may exhibit one or more selected sizes (e.g., unimodal, bimodal, or multimodal distributions). The one or more selected sizes may be determined, for example, by passing the diamond particles through one or more sizing sieves or by any other method. In an embodiment, the plurality of diamond particles may include a relatively larger size and at least one relatively smaller size. As used herein, the phrases “relatively larger” and “relatively smaller” refer to particle sizes determined by any suitable method, which differ by at least a factor of two (e.g., 40 μm and 20 μm). More particularly, in various embodiments, the plurality of diamond particles may include a portion exhibiting a relatively larger size (e.g., 100 μm, 90 μm, 80 μm, 70 μm, 60 μm, 50 μm, 40 μm, 30 μm, 20 μm, 15 μm, 12 μm, 10 μm, 8 μm) and another portion exhibiting at least one relatively smaller size (e.g., 30 μm, 20 μm, 15 μm, 12 μm, 10 μm, 8 μm, 4 μm, 2 μm, 1 μm, 0.5 μm, less than 0.5 μm, 0.1 μm, less than 0.1 μm). In another embodiment, the plurality of diamond particles may include a portion exhibiting a relatively larger size between about 40 μm and about 15 μm and another portion exhibiting a relatively smaller size between about 12 μm and 2 μm. Of course, the plurality of diamond particles may also include three or more different sizes (e.g., one relatively larger size and two or more relatively smaller sizes) without limitation.

In operation, the first force coupling assembly 102 may be coupled to a first movable component (e.g., a rotating shaft) and the second force coupling assembly 108 may be coupled to another movable component or tool (e.g., another rotating shaft or rotating component or tool). The force coupling assembly 100 may transfer or couple a force applied to the shaft (e.g., torque provided by a motor) to another movable component via the force coupling assembly 100.

As the force is applied, the contact surfaces 126 of the contact elements 104 will engage with the contact surfaces 136 of the contact elements 110. For example, the contact surfaces 126, 136 may engage with each other after at least some relative rotation between the first support structure 106 and the second support structure 112 (e.g., less than 1 degree to 15 degrees). Such rotation may occur as the force coupling assembly 100 is initially placed under a load or force (e.g., from the motor). As depicted, central portions of the contact surfaces 126, 136 may engage with each other (e.g., where the contact surfaces 126, 136 are loaded substantially in compression) in order to transfer forces between the first support structure 106 and the second support structure 112. In some embodiments, the contact surfaces 126, 136 may be at least partially rotational offset from each other, for example, while still contacting substantially at the center portions or may be entirely offset and interlocked as discussed below.

In additional embodiments, the contact elements 104, 110 may be configured to enable little to substantially no relative rotation between the first support structure 106 and the second support structure 112.

As depicted, the partially spherical shape of the contact surfaces 136 of the contact elements 110 may apply a point loading (e.g., in compression) to the contact surfaces 126 of the contact elements 104.

In some embodiments, the material of the contact surfaces 126, 136 may be selected to provide a coefficient of friction that will enable the contact surfaces 126, 136 to engage and remain substantially stational relative to each other once under loading.

In some embodiments, the shape of the contact surfaces 126, 136 may be selected to provide resistance to relative motion therebetween (e.g., an interference fit), where one or more of the contact surfaces 126, 136 includes a feature that engages the other surface and then limits or stops (e.g., ceases) further relative movement between the contact surfaces 126, 136. For example, as depicted, the cylindrical shape of the contact surfaces 126 of the first support structure 106, which exhibit a planar surface in a direction about the rotational direction of the force coupling assembly 100, may limit and/or substantially prevent the spherical shape of the contact surfaces 136 of the first support structure 106 from rotation relative to the contact surfaces 126 of the first support structure 106.

The shape of the contact surfaces 126, 136 may be selected to enable the first support structure 106 and the second support structure 112 to be assembled and disassembled by moving or positioning (e.g., sliding) one or the structures 106, 112 into the other of the structures 112 106, respectively.

As noted above, the relative shapes of the contact surfaces 126, 136 may be selected such that the first support structure 106 and the second support structure 112 may tilt relative to one another. For example, the depicted contact surfaces 126 having a partially substantially cylindrical shape may provide a substantially elliptical (e.g., circular) path on which the partially substantially spherical contact surfaces 136 may travel in a direction transverse (e.g., perpendicular) to the direction of rotation. In some embodiments, the partially substantially cylindrical contact surfaces 126 may enable at least some axial movement of the contact elements 110 to compensate for one or more of axial misalignment, tilt, and/or axial deflection (e.g., shaft deflection). For example, the contact surfaces 126 may allow for some axial translation and/or lateral movement resulting in rotation of the shaft to which the force coupling assembly 100 is coupled.

While the contact surfaces 126, 136 above are partially substantially cylindrical and partially spherical in shape, the contact surface 126, 136 may be selected as any suitable shape. For example, the contact elements 104, 110 may comprise contact surfaces 126, 136 of any combination of one or more of a substantially planar surface, a partially convex substantially spherical surface, a partially concave substantially spherical surface, a partially convex substantially cylindrical surface, a partially concave substantially cylindrical surface, or a surface defining a portion of an interlocking feature. Example embodiments of some of these configurations are discussed below.

FIGS. 4 and 5 are cross-sectional views of a portion of a force coupling assembly 200 including contact elements 204, 210 on opposing support structures 206, 212. The force coupling assembly 200 may be similar to and/or may include any feature or features of the various elements discussed herein, in any combination, without limitation.

As shown in FIGS. 4 and 5 , where the cross-sections are taken in substantially perpendicular directions to each other (e.g., with FIG. 4 depicting a cross section along a radial plane and FIG. 5 along an axial plane), the contact elements 204 on the inner support structure 206 may exhibit a slotted shape. For example, the contact elements 204 may exhibit a concave substantially elliptical shape (e.g., a partially substantially cylindrical shape) defining a concave substantially elliptical (e.g., circular) path. The contact elements 210 on the outer support structure 212 may exhibit a convex substantially elliptical shape (e.g., a partially substantially spherical shape).

As best shown in FIG. 4 , such a configuration may substantially limit rotation of the support structures 206, 212 relative to each other. For example, the partially substantially spherical shape of the contact elements 210 may be held in a lower portion of the concave partially substantially cylindrical contact elements 204 and be prohibited from rotation by the two raised side ramp portions of the partially substantially cylindrical contact elements 204.

As best shown in FIG. 5 , such a configuration may enable the support structures 206, 212 to tilt relative to each other, where FIG. 5 illustrates a tilted position. For example, the partially substantially spherical shape of the contact elements 210 may allow for displacement of the partially substantially spherical shape of the contact elements 210 along or away from a lower portion of the partially substantially cylindrical contact elements 204.

FIG. 6 is a cross-sectional view of a portion of a force coupling assembly 300 including contact elements 204, 310 on opposing support structures 206, 312. The force coupling assembly 300 may be substantially similar to the force coupling assembly 200 and/or may include any feature or features of the force coupling assembly 200, in any combination, without limitation. However, the contact elements 310 may also exhibit a partially cylindrical shape with the lower portion extending along the axial direction.

FIGS. 7 and 8 are cross-sectional views of a portion of a force coupling assembly 400 including contact elements 404, 410 on opposing support structures 406, 412. The force coupling assembly 400 may be similar to and/or may include any feature or features of the various elements discussed herein, in any combination, without limitation.

As shown in FIGS. 7 and 8 , where the cross-sections are taken in substantially perpendicular directions to each other (e.g., with FIG. 7 depicting a cross section along a radial plane and FIG. 8 along an axial plane), the contact elements 404, 410 may collection define an interlocking feature in at least one direction. For example, the contact elements 404 on the inner support structure 406 may exhibit a protrusion or post 414 and the contact elements 410 on the outer support structure 412 may exhibit a complementary recess or slot 416. In additional embodiments, the posts and recesses may be placed in reverse of that shown in FIG. 7 .

As best shown in FIG. 7 , such a configuration may substantially prohibit rotation of the support structures 406, 412 relative to each other. For example, the collective interlocking features of the contact elements 404, 410 may engage and substantially limit or substantially prohibit the contact elements 404, 410 from rotation. As depicted, the interlocking features of the contact elements 404, 410 may only substantially limit or substantially prohibit movement in one manner or direction (e.g., substantially prohibiting rotation while enabling axial movement or tilt).

As best shown in FIG. 8 , in some embodiments, such a configuration may enable the support structures 406, 412 to tilt relative to each other. For example, the partially substantially spherical shape of the contact elements 410 may exhibit a partially substantially spherical shape (e.g., a convex partially substantially cylindrical shape) and enable the contact elements 410 to move along the post 414 of the contact elements 404 regardless of the interlocking feature.

FIG. 9 is a cross-sectional view of a portion of a force coupling assembly 500 including contact elements 504, 510 on opposing support structures 506, 512. The force coupling assembly 500 may be substantially similar to and may include one or more features of the force coupling assembly 400, in any combination, without limitation. For example, force coupling assembly 500 may include one or more interlocking features. However, contact elements 504 on the support structure 506 may be offset from and interleave with contact elements 510 on the support structure 512 in order to provide an interference fit 514 (e.g., where at least some of the forces may be in tensile loading as one edge of the contact elements 504 is forced into an adjacent edge of the contact elements 510).

FIGS. 10 and 11 are cross-sectional views of a portion of a force coupling assembly 600 including contact elements 604, 610 on opposing support structures 606, 612. The force coupling assembly 600 may be similar to and may include one or more features of any of the various elements discussed herein, in any combination, without limitation.

As shown in FIGS. 10 and 11 , where the cross-sections are taken in substantially perpendicular directions to each other (e.g., with FIG. 10 depicting a cross-sectional view along a radial plane and FIG. 11 along an axial plane), in one embodiment, the contact elements 604 on the inner support structure 606 may exhibit a substantially planar contact surface. In such an embodiment, the contact elements 610 on the outer support structure 612 may also exhibit a substantially planar contact surface.

Such a configuration may substantially limit or prohibit rotation and tilt of the support structures 606, 612 relative to each other.

FIG. 12 is a cross-sectional view of a portion of a force coupling assembly 700 including contact elements 604, 710 on opposing support structures 606, 712. The force coupling assembly 700 may be substantially similar to and may include one or more feature of the force coupling assembly 600, in any combination, without limitation. However, the contact elements 710 may also exhibit a substantially elliptical shape, for example, a partially substantially cylindrical shape with the upper central ridge or portion extending along the axial direction. Such a configuration may enable at least some rotation of the support structures 606, 612 relative to each other along the curved portion of the convex partially substantially cylindrical surface of the contact elements 710. In additional embodiments, a partially substantially spherical shape may also be implemented on the contact elements 710.

In additional embodiments, the shape of the contact elements 604, 710 may be reversed and/or reorientated in order to enable tilt of the support structures 606, 712 in a similar manner to that discussed above (e.g., when the upper central ridge or portion is rotated 90 degrees).

FIG. 13 is a cross-sectional view of a portion of a force coupling assembly 800 including contact elements 804, 810 on opposing support structures 806, 812. The force coupling assembly 800 may be substantially similar to any of the force coupling assemblies discussed above and may include one or more features of any of the elements and/or materials described herein, in any combination, without limitation. As shown in FIG. 13 , each of the support structures 806, 812 may include one or more rows of contact elements 804, 810 (e.g., two rows, three rows, four rows or more, combinations thereof).

As depicted in FIG. 13 , such a configuration may enable axial movement between the support structures 806, 812 while at least some of the rows of contact elements 804, 810 remain in contact in order to couple the forces applied between the support structures 806, 812.

FIG. 14 is a partial cross-sectional perspective view of an exemplary assembly or system (e.g., subterranean or downhole system 900) that includes a force coupling assembly 901 (e.g., any of force coupling assemblies 100, 200, 300, 400, 500, 600, 700, 800). As shown in FIG. 14 , subterranean system 900 may include a housing 902 with a shaft (e.g., output shaft 904) that is directly or indirectly operably coupled to a rotational energy device, such as for example, a downhole drilling motor (e.g., a motor, turbine, or any other suitable device capable of rotating an output shaft, without limitation). In other embodiments, generally, force coupling assemblies, as disclosed herein, may be employed in rotating systems in a variety of applications (e.g., pumps, motors, turbines, generators, etc.) where transmission of forces (e.g., torque) is required.

For example, force coupling assembly 901 may be operably coupled to the output shaft 904 having an axis of rotation 906 (e.g., centerline, longitudinal axis) at a support structure of the force coupling assembly 901 (e.g., inner support structure 908) such that the force coupling assembly 901 rotates in conjunction with the output shaft 904. The force coupling assembly 901 may also be coupled to another movable component of the subterranean system 900 (e.g., another rotating shaft 910) at another support structure of the force coupling assembly 901 (e.g., outer support structure 914). The another rotating shaft 910 may have an axis of rotation 912 (e.g., centerline, longitudinal axis).

The respective shafts 904, 910 may be integral with or attached to (e.g., modular) the support structures 908, 914 of the force coupling assembly 901. For example, the respective shafts 904, 910 may be attached the force coupling assembly 901 (e.g., a respective one of the inner support structure 908 or the outer support structure 914) through brazing, press-fitting, threaded attachment, pin attachment, bonding, frictional engagement, splines, welding, keying, clamping, and/or by any other suitable attachment mechanism or structure.

In some embodiments, the outer support structure 914 and the shaft 910 may define a cup-shaped socket in which the inner support structure 908 with the shaft 904 attached thereto is received.

As discussed above, the contact elements of the force coupling assembly 901 may engage to couple a force (e.g., torque) applied to the output shaft 904 (e.g., by the motor) to the another rotating shaft 910.

As also discussed above, the force coupling assembly 901 may couple the torque between the output shaft 904 and the another rotation shaft 910 while the respective axes of the rotation 906, 912 are angularly offset or coincident. For example, as depicted, the output shaft 904 and the another rotation shaft 910 may be offset relative to each other with the respective axes of the rotation 906, 912 being angularly offset except for a point where the axes of the rotation 906, 912 intersect.

In some embodiments, rotating shaft 910 may in turn drive a downhole tool (e.g., a rotary drill bit, a reamer, etc.) configured to engage a subterranean formation.

Any of the force coupling assemblies disclosed herein may be used in subterranean system 900, without limitation.

According to various embodiments, drilling fluid may be circulated through the downhole drilling motor to generate torque and effect rotation of output shaft 904 and the rotating shaft 910 coupled to the output shaft via the force coupling assembly 901 so that a torque applied to the output shaft 904 may be transferred to the rotating shaft 910. In some embodiments, some of the drilling fluid may be in contact with the opposing contact surfaces of the force coupling assembly 901 for lubrication and/or cooling of the force coupling assembly 901.

Embodiments of the present disclosure may provide force coupling assemblies including mating surfaces comprising superhard material that enable the effective transfer of forces (e.g., torque) between components of a system at the engaged superhard surfaces. Such superhard materials may be implanted in caustic or corrosive conditions without having to be sealed or otherwise isolated from environmental elements, such as, for example, from the drilling fluid used during a downhole operation. In some embodiments, force coupling assemblies may enable at least some axial movement to compensate for one or more of axial misalignment, tilt, and/or axial deflection (e.g., shaft deflection) while still enabling the transfer of forces with the force coupling assembly.

While the present disclosure has been described herein with respect to certain illustrated embodiments, those of ordinary skill in the art will recognize and appreciate that it is not so limited. Rather, many additions, deletions, and modifications to the illustrated embodiments may be made without departing from the scope of the disclosure as hereinafter claimed, including legal equivalents thereof. Further, the words “including,” “having,” and variants thereof (e.g., “includes” and “has”) as used herein, including the claims, shall be open ended and have the same meaning as the word “comprising” and variants thereof (e.g., “comprise” and “comprises”). In addition, features from one embodiment may be combined with features of another embodiment while still being encompassed within the scope of the disclosure as contemplated by the inventors. 

What is claimed is:
 1. A torque coupling assembly, comprising: an inner assembly comprising: an inner support ring positioned circumferentially about an inner ring axis; and a first plurality of superhard contact elements coupled to the inner support ring, each of the first plurality of superhard contact elements having a superhard contact surface; and an outer assembly comprising: an outer support ring positioned circumferentially about an outer ring axis; and a second plurality of superhard contact elements coupled to the outer support ring, each of the second plurality of superhard contact elements having a superhard contact surface, wherein the superhard contact surface of at least one of the second plurality of superhard contact elements is configured to contact and transfer a torque to a respective superhard contact surface of at least one of the first plurality of superhard contact elements when a rotational force is applied between the inner assembly and the outer assembly.
 2. The torque coupling assembly of claim 1, wherein the inner assembly is configured move axially relative to the outer assembly when the rotational force is applied between the inner assembly and the outer assembly.
 3. The torque coupling assembly of claim 1, wherein the inner assembly is configured to rotate less than 15 degrees relative to the outer er assembly.
 4. The torque coupling assembly of claim 1, wherein the superhard contact surface of each of the second plurality of superhard contact elements contacts and is configured to remain in contact with one or more respective superhard contact surfaces of the first plurality of superhard contact elements when the rotational force is applied between the inner assembly and the outer assembly.
 5. The torque coupling assembly of claim 4, wherein the superhard contact surface of each of the second plurality of superhard contact elements is partially rotationally offset from the respective superhard contact surface of the first plurality of superhard contact elements when the rotational force is applied between the inner assembly and the outer assembly.
 6. The torque coupling assembly of claim 1, wherein, when the rotational force is applied between the inner assembly and the outer assembly, the inner assembly is configured to not substantially rotate relative to the outer assembly.
 7. The torque coupling assembly of claim 1, wherein, when the rotational force is applied between the inner assembly and the outer assembly, the inner assembly is configured to initially rotate relative to the outer assembly and then to cease rotating relative to the inner assembly once at least one of the first plurality of superhard contact elements engages with at least one of the second plurality of superhard contact elements.
 8. The torque coupling assembly of claim 1, wherein the inner support ring is configured to tilt relative to the outer support ring while at least some of the second plurality of superhard contact elements and at least some of the first plurality of superhard contact elements remain in contact with each other.
 9. The torque coupling assembly of claim 1, wherein at least some of the first plurality of superhard contact elements and the second plurality of superhard contact elements comprise at least one of polycrystalline diamond, a carbide material, or a nitride material.
 10. The torque coupling assembly of claim 1, wherein the superhard contact surface of at least some of the first plurality of superhard contact elements and the superhard contact surface of at least some of the second plurality of superhard contact elements comprise one or more of a substantially planar surface, a partially convex spherical surface, a partially concave spherical surface, a partially convex substantially cylindrical surface, a partially concave substantially cylindrical surface, or a surface defining a portion of an interlocking feature.
 11. A force coupling assembly, comprising: a first assembly comprising: a first support structure positioned circumferentially around a first structure axis; and one or more contact elements coupled to the first support structure, the one or more contact elements each having a superhard contact surface; and a second assembly comprising: a second support structure positioned circumferentially around a second structure axis; and one or more contact elements coupled to the second support structure, the one or more contact elements each having a superhard contact surface, the superhard contact surface of each of the one or more contact elements coupled to the second support structure opposing a respective one of the one or more contact elements coupled to the first support structure, wherein the superhard contact surface of at least one of the one or more contact elements coupled to the second support structure is configured to engage with a respective one or more contact elements coupled to the first support structure when a force is applied between the first assembly and the second assembly.
 12. The force coupling assembly of claim 11, wherein the first support structure is configured to tilt relative to the second support structure such that the first structure axis is offset from the second structure axis while at least some of the one or more contact elements coupled to the second support structure remain in contact with at least some of the one or more contact elements coupled to the first support structure.
 13. The force coupling assembly of claim 11, wherein the superhard contact surface of the one or more contact elements coupled to the first support structure and the superhard contact surface of the one or more contact elements coupled to the second support structure comprise one or more of a substantially planar surface, a partially substantially spherical surface, a partially substantially cylindrical surface, a surface defining a protrusion, or a surface defining a recess.
 14. The force coupling assembly of claim 11, wherein the one or more contact elements coupled to the first support structure and the one or more contact elements each comprise at least one of polycrystalline diamond, a carbide material, a silicon carbide material, a nitride material, or a silicon nitride material.
 15. The force coupling assembly of claim 11, wherein, when the force is applied between the first assembly and the second assembly, the first assembly is at least partially engaged with the second assembly and is configured to not substantially rotate relative to the second assembly.
 16. A rotary motion system, comprising: a shaft; a rotational energy device configured to apply torque to the shaft in order to rotate the shaft; and at least one force coupling assembly comprising the force coupling assembly of claim 1 operably coupled to the shaft and another component, the system configured to transfer at least some of the torque applied to the shaft by the rotational energy device to the another component of the system via the at least one force coupling assembly.
 17. The rotary motion system of claim 16, wherein the rotary motion system comprises a subterranean drilling system with the shaft being coupled to the another component comprising a downhole tool.
 18. The rotary motion system of claim 16, wherein the at least one force coupling assembly is either integral with or mechanically attached to the shaft.
 19. A method of transfer torque between components of a rotating system, the method comprising: applying a torque to a shaft in order to rotate the shaft about an axis of rotation; transferring the torque to another component coupled to the shaft with a torque coupling assembly, the transferring the torque comprising: applying the torque through a first ring coupled to the shaft, the first ring having one or more superhard coupling elements coupled to the first ring; and transferring the torque from the first ring through the one or more superhard coupling elements coupled to the first ring to one or more superhard coupling elements coupled to a second ring that is coupled to the another component; and rotating the another component with the torque.
 20. The method of claim 19, further comprising enabling the shaft to rotate relative to the another component about another axis of rotation by moving the one or more superhard coupling elements coupled to the first ring relative to the one or more superhard coupling elements coupled to the second ring in an axial direction along the axis of rotation.
 21. The method of claim 19, further comprising engaging the one or more superhard coupling elements coupled to the first ring with the one or more superhard coupling elements coupled to the second ring during the rotation such that the one or more superhard coupling elements coupled to the first ring remain substantially stationary relative to the one or more superhard coupling elements coupled to the second ring along a path of rotation about the axis of rotation. 